To validate models currently used to predict metastatic renal cell carcinoma (mRCC) outcomes in a cohort of patients undergoing cytoreductive nephrectomy (CN).

Ten renal cell carcinoma (RCC) prognostic models (International Metastatic RCC Database Consortium [IMDC]; Memorial Sloan Kettering Cancer Center [MSKCC]; Culp; Leibovich; University of California at Los Angeles Integrated Staging System [UISS]; Stage, Size, Grade, and Necrosis [SSIGN]; Yaycioglu; Karakiewicz; Cindolo; and Margulis) were chosen based on clinical relevance and use in clinical trial design.